Stockholders' Equity (Schedule of Dividend Increases) (Details) - $ / shares	1 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Jul. 31, 2013	Apr. 30, 2013
Schedule of Dividend Increases [Line Items]
Percent increase in common stock dividend	20.00%	39.00%	100.00%	20.00%
Common Stock, Dividends, Per Share, Board Increase Announcement, Quarterly	$ 0.300	$ 0.250	$ 0.180	$ 0.090
Common stock, Dividends, Per Share, Board Increase Announcement, Annual	$ 1.20	$ 1.00	$ 0.72	$ 0.36

Annualized amount of new quarterly dividend payment per share as approved by the board of directors.

No definition available.

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Namespace Prefix:	ce_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration